The present invention relates, in general, to a deep drawing method, and to a deep drawing machine for carrying out the method.
Nothing in the following discussion of the state of the art is to be construed as an admission of prior art.
In general, deep drawing machines involve a type of shaping tool having tools which move generally rectilinear and respectively include dies between which a sheet metal blank can be formed into a suitable cup-shape to assume the desired shape. Examples include crank presses, eccentric presses, hammers, and hydraulic presses. Shaping of metals, in particular sheet metals, typically involves the use of presses in which the die and the plunger moving the die undergo a rectilinear closing motion. Also the opening motion is executed along a straight line.
German Offenlegungsschrift DE 199 21 176 A1 describes a press for making irregularly curved sheets. The press includes an upper die and a lower die which are both configured with a plurality of height-adjustable cables arranged in rows in length direction and transverse direction and which are controllable independently from one another. This press is complicated in structure, and the design of the cable contact surfaces in the contact area to the sheet metal being shaped is difficult to realize in order to attain a desired surface quality of the metal blank.
It would therefore be desirable and advantageous to provide an improved deep drawing method and improved deep drawing machine to obviate prior art shortcomings and to allow manufacture of irregular sheets in a single operating cycle.